1. Field
Disclosed herein are slipform cast concrete products and to slipform casting apparatus used in casting, as well as parts for forming the products to be cast. More precisely, disclosed herein are methods for adjusting and changing the product height of a product to be slipform cast.
2. Description of Related Art
There are many different slipform casting methods and devices known in the art. The most essential slipform casting solutions in use nowadays are generally based on extruder or slipformer methods. In the solutions based on the extruder technique, the concrete mix is fed from the concrete tank to feed screws that extrude the concrete to the mold defined by the casting bed and the side and upper plates. When casting hollow-core slabs, the feed screws are followed by hollow-core forming mandrels forming the hollow-cores to the concrete product to be cast. The compacting of the concrete product to be cast is effected by the vibrating and/or leveling motion of the side and upper plates and the forming of the hollow-core is secured by the compacting motion of the hollow-core mandrel. The casting machine moves along the casting bed driven by the reacting force, supported by the wheels of the machine. The finished cast product remains on the casting bed.
In the solutions based on the slipformer-technique, the concrete mix is fed by proceeding to cast first to the lower part of the mold defined by the side plates moving along with the casting machine and the casting bed. This first feed of the concrete is followed by vibrating shoes and forming mandrels that, by vibrating the concrete mix, compact the cast concrete mix and make the final form of the lower part of the product. During a second feed, concrete mix is fed onto the end parts of the hollow-core forming mandrels for casting the upper part of the product to be cast, said concrete mix to be compacted with a vibrating pate located on top of the rear end. The finished product remains on the casting bed.
The slipform casting is usually used for casting of longitudinal products, which then are sawn to form products having a suitable length after hardening of the concrete.
A problem with the slipform casting devices known in the art is, however, that when the thickness of the product to be cast changes, the casting machine must be lifted away from the casting bed for changing the tools for forming the product and the tools for compacting. This is time consuming and expensive due to the production downtimes caused by the changes.
Another alternative has been to provide a specific casting machine for each product type to be cast, whereby the change of the product to be cast can be performed quickly simply by changing the casting machine on the casting bed. This alternative, however, requires a lot of capital investments in equipment, especially, because the product range of the products to be cast is typically large.